In almost all of the mosques here, Witr is prayed in congregation after the 20 rakah Taraweeh prayer. But as far as I know, Witr is to be prayed after Tahajjud if someone wishes to pray Tahajjud. So I was wondering, what is the ruling about it? Should I just sit and ignore the Witr congregation because I want to pray the Tahajjud later in night?